"ring-shaped," 1570s, from French annulaire (16c.) or directly from Latin annularis "pertaining to a ring," from annulus, diminutive of anus "ring" (see anus). An annular eclipse (1727) is one in which the dark body of the moon is smaller than the disk of the sun, so that at the height of it the sun appears as a ring of light. Related: Annularity.